What is the status of vocalisations which have been slowed down?

A study has shown that when mockingbirds imitate whip-poor-wills, they reproduce the full pattern revealed by altering the speed, implying that these 'hidden' sounds are audible to the avian ear, with its structure quite different from that of mammals - just as the syrinx, or avian vocal chord, is quite differently structured to our own, allowing two separate vocal lines to be sung simultaneously

Robert Dooling's experiments with synthetic sound patterns indicate that birds have a remarkable ability to detect rapid change: as the speed at which two notes alternate increases, humans at some point begin to hear them as a chord; birds, by contrast, continue to hear separate sounds, down to durations of close to a millisecond

This implies that birds hear and process song very quickly. The audio content of song may be exceptionally compressed as a result. On slowing down, the isolated cheeps and tweets of small birds often turn out to contain rich rhythmic and melodic material.

Applied to an entire audio field, as in the field recordings of bees and birds from the Cap de Creus, Catalunya, slowing results in a 'Southern', even 'Tropical' soundscape. Lower pitches and slower tempos recall the vocalisations of larger birds and animals.

We may consider that different kinds of organisms, with their various processing speeds, live alongside one another at different rates, evoking a landscape populated with numerous parallel channels, in no obvious hierarchy of perception

Of course it was Braque who showed how the silent call of a bird, introduced in the late great studio paintings, has the capacity to galvanise the canvas, prefiguring an actual tear or slash

In one of those nocturnal reveries that continue to exert their hold over us, shortly before his death, Hardy foresees the sinking of the Titanic in the meeting of two insects on his paper

After watching a video of a nightingale singing at quarter speed in the arches under London Bridge station, some people commented that the original playback speed now looked and sounded too fast